Shin represented the 21st District, which includes parts of Edmonds, Mukilteo, and parts of Everett and Lynnwood.

Shin, 78, was a college professor for 31 years, teaching East Asian studies at a variety of schools including the University of Washington, Western Washington University and Shoreline Community College. He was elected to the state House in 1992 and served two years, before stepping down for an unsuccessful run for Congress. He was elected to the state Senate in 1999.

Here’s the statement he issued Tuesday afternoon:

To my family, friends, colleagues, and residents of Washington State,

It is with deep regret that I must inform my constituents and the people of Washington State of my decision to resign from the Washington State Senate, effective immediately. Although I had planned to retire from the Legislature at the end of my term later this year, I have reluctantly determined with the assistance of my family that recent health problems including my age, memory problems, and a recent diagnosis of Alzheimer’s make it impossible for me to represent my constituents in the manner in which they deserve. I believe it is in everyone’s best interest — my family, my constituents, the Senate, and the great State of Washington — for me to step down at this time.

I would like to take this opportunity to thank all of you for your help and support over the years. It has been a tremendous privilege to be a member of the State Senate and work with such wonderful colleagues. I am grateful for the camaraderie, the work we accomplished, and the valuable lessons learned. I would also like to thank my wife and children for their love, support, and shared belief in the importance of service. Most of all, I would like to express my thanks to the citizens of the 21st Legislative District, who placed their trust in my stewardship for all of these years; it has been my honor and privilege to serve them for the past 17 years. I look forward to assisting the Senate in making this transition as smooth as possible.